Mr Lewis says Ms Knowlton was one of two from about 35 people in the class for a "shoot/don't shoot" simulation during which they decide whether to use simulated lethal force during a "live role play".

The chief says she was mistakenly shot with a live round. He says she was taken to a hospital, where she was pronounced dead.

Mr Lewis did not identify the officer involved. He has been placed on administrative leave pending a Florida Department of Law Enforcement investigation.